This study aims to determine problems of the damage investigation system of aquaculture products resulting from natural disaster and to deduce improvement plans for such problems. The main problems revealed from this study were as follows: 1) detailed damage investigation is carried out only by one particular organization, 2) for aquaculture insurance subscribers another detailed damage investigation is conducted to reveal the causes of natural disaster by a joint investigator team formed according to a different legislation with a different purpose, 3) damage investigation is usually suffered from lack of labor, budget and time due to the restriction of natural damage to a certain period of season leading to the absence of quick reaction capability for irresistible natural disasters, and 4) there are no specified procedures and protocols for deciphering causes of a natural demage. The improvement plans to find solutions for such problems are as follows: 1) for the investigation, the object, method and role of the investigation organization should be clarified by improving the present legislation, 2) investigation methods for determining the demage causes should be systematized by making a manual to minimize disputes, and 3) supports for the investigation organization should be institutionalized to guarantee sufficient budget and manpower. Under the present circumstance with continuous natural damages, smooth procedures of damage compensation would lead to the management stability of aquaculture farms.

In 2017 Pohang Earthquake, a number of residential buildings with pilotis at their first level were severely damaged. In this study, the results of an analytical investigation on the seismic performance and structural damage of two bearing wall buildings with pilotis are presented. The vibration mode and lateral force-resisting mechanism of the buildings with vertical and plan irregularity were investigated through elastic analysis. Then, based on the investigations, methods of nonlinear modeling for walls and columns at the piloti level were proposed. By performing nonlinear static and dynamic analyses, structural damages of the walls and columns at the piloti level under 2017 Pohang Earthquake were predicted. The results show that the area and arrangement of walls in the piloti level significantly affected the seismic safety of the buildings. Initially, the lateral resistance of the piloti story was dominated mainly by the walls resisting in-plane shear. After shear cracking and yielding of the walls, the columns showing double-curvature flexural behavior contributed significantly to the residual strength and ductility.

In this study, several approaches in evaluating moisture sensitivity of asphalt mixtures were investigated and compared. To evaluate the moisture damage resistance, twenty types of asphalt mixtures with and without anti stripping additives were tested in the laboratory. Uniaxial compressive strength (UCS) and indirect tensile (IDT) testing were performed to determine the Tensile Strength Ratio (TSR) and Cohesion Strength Ratio (CSR). Stone Mastic Asphalt (SMA) mixtures were found to provide good moisture damage resistance compared to other mixtures. It also does not require anti stripping additives to improve its moisture resistance. Moreover, the correlation coefficient between the TSR test and CSR tests is 0.99 with an average error of 1.5%, which indicates that the TSR test following AASHTO T-283 is still the most reasonable criteria in evaluating the moisture damage of AC mixtures. Marshall Stability Ratio (MSR) and Marshall Stability to Flow Ratio (MSFR) were conducted and were compared to TSR test results. It was found that MSFR value may be used to evaluate the moisture damage resistance of AC mixtures instead of TSR test. Finally, Dynamic Immersion (DI) test was performed to evaluate moisture resistance for loose asphalt mixtures. The DI results showed good correlation also when evaluating moisture resistance compared to TSR. When using DI testing in evaluating moisture resistance, it is recommended to test after 48 hours since it showed higher correlation with the TSR values. Further study is recommended to improve current testing evaluating moisture susceptibility of asphalt mixtures to properly associate it with TSR values.

In the present study, the impact of RO polyamide layer by long-term chemical exposure was evaluated. Basic cleaning chemicals such as NaOH increased the pure water flux and salt passage of RO membrane up to 1.6 times and 2 times, respectively. In contrast, membranes exposed to acidic chemicals such as HCl have experienced no discernible change of permeability, which indicated that basic chemicals caused the more serious damage to RO polymeric layers. However, XPS analysis showed that both membranes were experienced significant damages on cross-linking of polyamide structures. It can be concluded that basic cleaning chemicals induced the enlarged pore structure due to electrostatic repulsion between damaged polymers, while acidic chemicals caused less performance deterioration by shrinkage of the polyamide structure.

In this study, refined finite element (FE) analyses intended to evaluate the capacity of the existing water purification plant structures against seismic force are conducted with an aim to predict possibility generating tension crack and compression crushing. The FE models for three types of main plant structures were constructed to take ground condition, boundary condition, and water interaction into consideration for advanced simulation. The nonlinear dynamic analyses were performed by using ground motion data which have been used for seismic design. Both compression crushing and tention crack, which are distributed over concrete plant structures during peak ground acceleration (PGA), are investigated by analyzing failure possibility controlled with the strain limits. After observing FE analysis results, it is possible to predict tenstion cracking which can be found at some parts of the main structure.

Results of this study appeared chicken breeding households nationwide in 3,323 households. Local broiler breeding two numbers are Jeonbuk>Chungnam>Jeonnam> Gyeonggi>Gyeongbuk>Chungbuk>Gyeongnam>Gangwon>Jeju appeared in other net. Local chicken breeding numbers are Chungnam>Jeonbuk>Gyeongbuk>Jeonam> Chungbuk>Gyeongnam>Gangwon appeared in order. Livestock mortality is 482,000 numbers in 2012, and 911,000 numbers in 2014 and 2.494,000 numbers in 2015, a significant increase year by to 4.298,000 numbers in 2016. Insurance 11.2 billion in 2012, 49.8 billion in 2013, 21.2 billion in 2014, 74.5 million won was paid in 2015 is expected to be paid in 2016, 128.4 billion won. A study on the future, preventing livestock damage caused by high temperature will have to continue.

Recently, due to advancement in construction techniques, structures are being constructed much faster than before. Therefore, structures such as cable stayed bridges and suspension bridges, must be inspected regularly to assure their main elements (i.e., load carrying cables) are healthy and sound. Structures can be tested using conventional nondestructive testing methods such as magnetic flux leakage (MFL), eddy current testing, acoustic emission and etc. In this study, it was tried to detect cross sectional reduction in steel rod using a time dependent numerical simulation of coil sensor based on MFL principle.

Recently, localized rainfalls and torrential typhoons due to the abnormal climate have increased in Korea and the damage situation caused by debris flow at Umyeon Mountain has especially take place a big social issue. However, the standardized damage investigation does not yet exist and the systematic analysis of the data has not also been carried out. In this regard, this study developed assessment factors to conduct standardized damage investigation for debris flow. To achieve this, preliminary assessment factors were derived from analysis of literature review and the Delphi method through 12 experts who work at fields of facility, academia and industry. As a result, 29 rational check lists of 6 groups were determined.

This study carried out an investigation about damage characteristic of substructure such as pier and abutment of highway bridge. The applied methodology was the average damage analysis according to service life. By using above methodology, damage characteristic of substructure penetrated water included de-icing salt was investigated. It was found that the area where was under heavy snow exhibited higher amount of average damage than that of the area where was under much less snow.

The damage cases by debris flow and each investigation techniques used by the institutes associated with debris flow were analysed. It was concluded that considering urban debris flow characteristics and the purpose of investigation is essential to establish reasonable debris-flow damage investigation technique.

The highway bridges required the maintenance have been consistently increased over 8,000. For long term maintenance strategy, it should be focused on utilizing the systemic information from in-depth inspection data. From now, record-based inspection for highway bridges has been usually performed so that it is needed to investigate the in-depth inspection data for identifying the damage characteristics in detail. In this study, with respective to the performance measure of damage characteristic, damage normalization of highway bridges is researched by using the suggested bridge scales such as area, length, vertical distance, number of members. Based on this process, the standard cost for various damages for highway bridges can be estimated and utilized for long-term maintenance strategy.

This paper reviewed on the minimum strength of concrete in cold climates from the viewpoint of durability. The results show that the minimum strength to prevent early frost damage recommend to 21 MPa.